Comparison of Extraction Techniques with Different Solvents for DDT Analogues in Sediments

Four techniques, Soxhlet extraction (SOX), ultrasonic extraction (USE), fluidized-bed extraction (FBE) and acce-lerated solvent extraction (ASE) with different solvents (methanol, hexane/acetone and acetonitrile) were used for theextraction of DDT analogues in sediments. Results revealed that the four extraction techniques had high recoveries (>86.0%) with low standard deviations (< 12.0%) for most of DDT analogues, meaning that they could all successfully extractDDT analogues in sediments. Accelerated solvent extraction using methanol and hexane/acetone (1:1), fluidized-bedextraction using hexane/acetone (1:1) and the ultrasonic extraction using hexane/acetone (1:1) were comparable or betterthan Soxhlet extraction using hexane/acetone (1:1). Considering solvent- and time-consumption, level of automation,and environmental risk, accelerated solvent extraction with hexane/acetone (1:1) was better than the other extractiontechniques.

A NEW SINGULARITY EXTRACTION TECHNIQUE FOR TDEFIE

A new singularity extraction technique is presented to calculate accurately the singular integrals in Time Domain Electric Field Integral Equation (TDEFIE).In singularity extraction pro- cedure,through the aid of the first order Taylor series of time base function including time-retardation,the singularity of the integrand can be removed.The surface current density and backscattered far-field response of a conducting cube illuminated by a Gaussian plane wave is com- puted using the presented technique.Comparisons are made with the results obtained by the Inverse Discrete Fourier Transform (IDFT) of the frequency domain and the results obtained by using Ve- chinski's time averaging technique,which demonstrate that the presented method with this new time domain singularity extraction technique to solve TDEFIE is very accurate and stable.

Study on Extraction Techniques of Celastrol from Celastrus orbiculatus Thunb.

[Objectives]This study was conducted to investigate the extraction technology of celastrol from Celastrus orbiculatus Thunb.[Methods]Solvent ultrasonic extraction was selected,and with the content of celastrol as the evaluation index,the effects of different solvents,extraction time,temperatures and material-to-liquid ratios on the extraction rate of celastrol were investigated by single factor and orthogonal experiments.[Results]The optimal extraction conditions were as follows:a solvent ratio of petroleum ether to ethyl acetate at 1∶1,a ratio of solvent to material at 10∶1(v/w),extraction time of 30 min,and an extraction temperature at 30℃.[Conclusions]This method has high extraction rate,and is simple and feasible.

Injection and Extraction Techniques in Circular Accelerators

Injection and extraction are usually the key systems in circular accelerators.They play important roles in transferring the beam from one stage acceleration to the other or to experimental stations.It is also in the injection and extraction regions where beam losses happen mostly.Due to the tight space and to reduce the perturbation to the circulating orbit,the devices are usually designed to meet special requirements such as compactness,small stray field,fast rise time or fall time,etc.Usual injection and extraction devices include septum magnets,kicker magnets, electrostatic deflectors,slow bump magnets and strippers.In spite of different accelerators and specification for the injection and extraction devices,many techniques are shared in the design and manufacturing.This paper gives a general review on the techniques employed in the major circular accelerators in China.

A review on the extraction and separation of andrographolide from Andrographis paniculata:extraction selectivity,current challenges and strategies

Andrographolide is the main active ingredient of Andrographis paniculata(Burm.f.)Nees,known as“natural antibiotic”.Here,for the purpose of discovering a more efficient,low-cost extraction and separation method,the research status of andrographolide was reviewed.At present,researches only take extraction rate as the only index to optimize extraction parameters,but ignores the importance of extraction selectivity.It is usually meaningless to blindly pursue the extraction rate without considering the difficulty and cost of subsequent separation.So,factors affecting extraction selectivity such as solvent choice,temperature and physicochemical effects caused by extraction technique itself,are first discussed.Different extraction techniques for andrographolide were discussed by comparing the selectivity,efficiency and cost of extraction.The separation procedures of andrographolide such as decolorization,impurity removal,crystallization,membrane separation,solid-phase extraction and partition chromatography and their challenges and possible strategies are also discussed.It is hoped that this review can provide guidance for researchers who are committed to advancing the field of andrographolide extraction and purification.

Extraction and Antioxidant Functions of Polysaccharides from Seaweed

Dried seaweed powder was used as the raw material to extract polysaccharides by ethanol precipitation after water bath. Extraction temperature, extrac- tion duration, solution pH and solid to liquid ratio were selected as technical parameters which required to be optimized. With the extraction rate of seaweed poly- saccharides as an index, single-factor experiment and orthogonal experiment were carried out to determine the optimal extraction technique. Seaweed polysaceharides were extracted with the optimal technical parameters to analyze the biological activities. Savage method was used to process seaweed polysaceharide extract. In vitro biological activities of preliminarily purified seaweed polysaeeharides were investigated successively, including reducing ability, antioxidant ability and antibacterial activity. The results showed that there was a positive correlation between polysaccharide concentration and its reducing ability, antioxidant ability and antibacterial activity. Furthermore, there was also a correlation among the reducing ability, antioxidant ability and antibacterial activity of seaweed polysaecharides; the relation- ship between each two of these three indicators was similar to positive linear correlation.

Evaluating the performances of accelerated-solvent extraction, microwave-assisted extraction, and ultrasonic-assisted extraction for determining PCBs, HCHs and DDTs in sediments

Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments, i.e. accelerated solvent extraction （ASE）, microwave assisted extraction （MAE） and ultrasonic assisted extraction （UAE）. However, their extraction efficiencies have rarely been quantitatively compared using rigorous mathematical methods. In this paper, one-way analysis of variance （ANOVA） was employed to evaluate the performance of ASE, MAE and UAE in the overall extraction of PCBs, DDTs and HCHs by analysis of their recoveries from the Standard Reference Material IAEA-417, a sediment sample certified by many international laboratories. Conclusions were drawn at a significance level of P〈 0.05. No significant differences were found among the mean values for method recoveries using ASE, MAE and UAE. The mean values for real recoveries using ASE and MAE were nearly identical, but the real recovery using UAE was much lower. The concentrations of all PCBs, DDTs and HCHs except for CB52 and o,p＇-DDT using UAE were the lowest. Comparing the results obtained using ASE with MAE, the concentrations of CB28, CB52, CB138, ct-HCH, [3-HCH, p,p＇-DDE and p,p＇-DDD were nearly identical, while the concentrations of other compounds were significantly different. Based on the low recoveries, it was concluded that UAE is a relatively inefficient extraction method, while ASE and MAE are equivalent methods. Taking into consideration the relative standard deviation （RSD） values, solvent volume, extraction time, and purchasing costs of the apparatus, MAE was considered superior to ASE for extraction of PCBs, DDTs and HCHs.

Ultrasonic wave extraction and simultaneous analysis of polycyclic aromatic hydrocarbons (PAHs) and phthalic esters in soil

A method is developed for detection of polycyclic aromatic hydrocarbons(PAHs) and Phthalic Acid Esters(PAEs) in soil samples. Ultrasonic Wave Extraction under airtight circumstances is adopted to extract the analytes in soil samples with n-hexane–acetone(V:V=1:1) as extraction solvent. This method has several advantages, including high extraction efficiency, short time, convenience and simplicity. It can be used to detect polycyclic aromatic hydrocarbons(PAHs) and Phthalic Acid Esters(PAEs) in soil.

Early Diagnosis of Lung Tumors for Extending Patients’ Life Using Deep Neural Networks

The medical community has more concern on lung cancer analysis.Medical experts’physical segmentation of lung cancers is time-consuming and needs to be automated.The research study’s objective is to diagnose lung tumors at an early stage to extend the life of humans using deep learning techniques.Computer-Aided Diagnostic(CAD)system aids in the diagnosis and shortens the time necessary to detect the tumor detected.The application of Deep Neural Networks(DNN)has also been exhibited as an excellent and effective method in classification and segmentation tasks.This research aims to separate lung cancers from images of Magnetic Resonance Imaging(MRI)with threshold segmentation.The Honey hook process categorizes lung cancer based on characteristics retrieved using several classifiers.Considering this principle,the work presents a solution for image compression utilizing a Deep Wave Auto-Encoder(DWAE).The combination of the two approaches significantly reduces the overall size of the feature set required for any future classification process performed using DNN.The proposed DWAE-DNN image classifier is applied to a lung imaging dataset with Radial Basis Function(RBF)classifier.The study reported promising results with an accuracy of 97.34%,whereas using the Decision Tree(DT)classifier has an accuracy of 94.24%.The proposed approach(DWAE-DNN)is found to classify the images with an accuracy of 98.67%,either as malignant or normal patients.In contrast to the accuracy requirements,the work also uses the benchmark standards like specificity,sensitivity,and precision to evaluate the efficiency of the network.It is found from an investigation that the DT classifier provides the maximum performance in the DWAE-DNN depending on the network’s performance on image testing,as shown by the data acquired by the categorizers themselves.

Research Progress of Total Flavonoids from Plants in Trib.Lorantheae

Trib.Lorantheae is one of the important medicinal plants in traditional medicine.There are 41 genera,6 genera of which are produced in China,mainly distributed in Southwest China,South China and Central South China.There are many kinds of plants in this family,and 22 species can be used as Chinese medicinal materials in China.The branches and leaves of Trib.Lorantheae are rich in flavonoids,alkaloids,terpenoids,polysaccharides,organic acids and other functional substances,among which flavonoids are one of the important chemical components to exert pharmacological activity,and play an important role in hypoglycemic,lipid-lowering,anti-inflammatory,anti-tumor,anti-oxidation,anti-osteoporosis and so on.In this paper,the chemical composition,extraction method,component analysis and pharmacological action of flavonoids in Trib.Lorantheae plants were reviewed,in order to provide scientific reference for further development and clinical application of flavonoids in Trib.Lorantheae plants.

Green Extraction of Bioactive Compounds from Microalgae

At present,there is an increasing demand for natural bioactive compounds able to provide health benefits when included and consumed in a functional food or in a nutraceutical.In this regard,microalgae are promising natural sources with great potential,not only considering that these organisms are largely underexplored,but also because microalgae can be produced at large scale and their chemical composition might be tuned to over-synthesize a particular target compound.The use of advanced sustainable extraction techniques to recover these bioactive compounds is a must nowadays.This work presents an overview on the use of compressed fluid-based extraction techniques to obtain bioactive compounds from microalgae that can be seen also as a first step towards its recovery at larger scale.When relevant,the description of the analytical procedure used to chemically characterize the bioactive compounds is also included.

Citrus reticulata Blanco (the common mandarin) fruit:An updated review of its bioactive,extraction types,food quality,therapeutic merits,and bio-waste valorization practices to maximize its economic value

Fruits are regarded as the richest dietary sources of polyphenols,carotenoids,terpenoids,and limonoids,making them highly desired prospects for the functional food industry.Citrus waste that remains after fruit processing is also regarded as a valuable source of value-added phytochemicals.A comprehensive analysis of mandarin composition as a determinant of fruit functional properties,health benefits,and valorization into useful products is represented together with the effect of different processes such as light,wax coating,auxin addition,ozone treatment,and ethylene degreening.Such reviewing evidence is an essential precondition for improving the selling market of mandarin and highlighting its waste valorization potential and its incorporation into useful products produced by pharmaceutical industries.In this study,the phytochemical and biological reports presented to emphasize the needed priority for agricultural techniques to provide a certain mandarin product or trait.In addition,the paper summarizes the optimum conditions applied for the updated extraction techniques for phenolic acids,flavonoids,and oils at a commercial scale from mandarin peels and to enhance its global marketing.A brief representation is given towards potential mandarin patents and the valorization of its bio-waste fruits into commercial products of added value.The review can guide researchers to produce future potentially marketed functional food enriched with mandarin extracts and/or bioactives.

Atmospheric Drying UHMWPE Membranes via Multiple Stage Extractant Exchange Drying Technique

Ultra-high molecular weight polyethylene(UHMWPE)membranes were prepared by 5 wt%UHMWPE/parafn oil gels via thermally induced phase separation method and dried in air without signifcant collapse.The UHMWPE membranes were annealed at 110℃ for increasing the pores size in order to decrease the capillary forces.Furthermore,a new multiple stage extractant exchange drying(MSEED)technique was adopted to decrease the shrinkage of the UHMWPE membranes.Specifcally,the parafn oil was extracted by dichloromethane,then dichloromethane was replaced by ethanol,next ethanol could be exchanged to other liquid which is non-afnity with UHMWPE,for example water.UHMWPE membranes(annealing for 25 min)dried by dichloromethane-ethanol-water-air process have the lowest volume shrinkage of 16.5%and the porosity is as high as 88.29%.Moreover,compared with supercritical CO_(2)(SC-CO_(2))drying,atmospheric drying UHMWPE membranes have a lower pure water permeance,but a higher carbon particles rejection.

On the applicability of the‘humic acids’nomenclature from natural ecosystems to engineering sciences

‘Humic acids(HA)’are the major constituents of natural organic matter(NOM)derived from the plant or biological residues by decomposition and synthesis in natural ecosystems.They have been defined as relatively high molecular weight aggregates of macromolecules associations with series of highly reactive functional compounds,and considered to be as irreplaceable roles(such as the impact on global carbon and nitrogen dynamics,atmosphere,living plants,chemically reactive and NOM structure stabilization)in natural ecosystems[1].